1. Technical Field
The invention relates to a method of calibrating a position offset of a cursor, and more particularly to a method for compensating the position offset of a cursor according to calculating boundary offset value of the cursor on a screen.
2. Description of Related Art
Owing to evolution of input devices for use with computers, a mouse is an input pointing device almost indispensable to computers nowadays. A user quickly moves a cursor on a screen of a display device connected with a computer to any icons or options displayed thereon, by moving a mouse. A plenty of input pointing devices such as wireless pointing devices and methods such as eye movements have hitherto been developed for controlling cursor movement.
However, a problem encountered in controlling cursor movement with whatever input pointing devices remains unsolved. As time passes, a position offset between an input pointing device and a cursor increases with errors and thus accumulates, thereby bringing inconvenience to a user. The problem is hereby exemplified by a mouse—an input pointing device in wide use. Referring to FIG. 1, a mouse 12 is moved by a user in the direction of A1, a cursor 10 will move in the direction of A1 in tandem with the input pointing device until the cursor 10 on the screen 11 reaches a boundary and stops. At this moment, if the mouse 12 is further moved in the direction of A1, the cursor 10 on the screen 11 will stay at the boundary of the screen 11. However, if the mouse 12 is moved in the direction of A2, the cursor 10 will instantly start to move in the direction of A2 in tandem with the cursor 10. After several instances of the aforesaid operation, the mouse 12 increasingly burdens the user's grip thereon, because the mouse 12 is moving away from the center of a mouse pad 13 gradually and inevitably. In an attempt to fix the problem, the user usually lifts the mouse 12 slightly, rests the mouse 12 on the mouse pad 13 again, and repositions the mouse 12 at the center of the mouse pad 13, before proceeding with operation of the cursor 10.
Likewise, the aforesaid problem occurs to other input pointing devices for controlling a cursor. For instance, in addition to general computer operation, wireless pointing devices, which are commercially available and in wide use, are applicable to interactive games developed for Wii or PS2 platforms. Hence, a wireless pointing device is an indispensable accessory for game players. As time passes, a game player is eventually confronted with a position offset between his/her wireless pointing device and the cursor on the screen. In an attempt to eliminate the position offset, the game player usually takes a break and, during the break, realigns the wireless pointing device with the cursor on the screen before proceeding with the games. Therefore, a position offset has a negative impact on input pointing devices regarding ease of use of the input pointing devices and the quality of the games being played.
Hence, it is imperative to resolve the problem of a position offset between a pointing device and a cursor on a screen, so as for users to operate whatever pointing devices smoothly without the hassle of lifting a mouse, realigning the mouse, or repositioning a wireless pointing device during the user's operation.